THE ROLE OF COAGULANT IN CHEESE MAKING

• The proportion of rennet added should be the minimum necessary so as to get a firmer coagulum within 30 – 40 min duration.
• Addition of calcium chloride or increase in the temperature at which rennet is added for coagulation may be resorted to off set the seasonal variations in the milk composition.
• During clotting, the casein micelles, which are separate initially aggregate into a network, coalesce and finally form a granular mass.
• Similarly, the fat globules which are separate in the beginning are forced together into a compact mass because of the shrinkage of the casein network.
• When the rennet coagulu is cut, the surface of the fat globules is exposed and some of them are washed out as the curd is being stirred. This gives rise to a thin layer of depleted fat at the curd-granule interface.
• During the process of matting, the layers of adjoining curd granules fuse resulting in the formation of fat depleted junctions.
• Starter cultures or bacteria are trapped in the casein network near the fat – casein interface. This region is thought to hold highest moisture content in the mature or ripened cheese mass.